Wade's comment above struck a cord with me - the move to NAS in the lower to mid-shelf is a mark of the industry responding to exploding demand and holding onto their shelf space. You lose that space, and it may be hard to get back.
Further, it also seems clear to those on the board here who have been drinking bourbon much longer than I have that the ability to go NAS and maintain the age-stated taste is difficult if not impossible over the medium to longer term, both because of the increased demand and the trend of taking whatever available older whiskies that might balance a NAS bottling and put into age-stated higher priced brands. As the shelves are cleared of the age-stated version and bunkered, it will remain to be seen if these NAS bottlings will hold onto those who are now finding an interest in bourbon and move them up the shelf, or whether they'll just shrug and say, it's just OK and go back to whatever they were drinking beforehand.
If five- or 10-years hence the demand stabilizes or cools, I think you'll see "improved" NAS bottlings and perhaps some age statements return. But it is clear that most of the move to NAS leaves something to be desired - look at all of the blends experimented with on this board which I think is at least an attempt at recreating what was (SB Blend a notable example).